Due to its advantages of energy conservation and environmental protection, electric vehicles have become the trend of development of automobiles in the future.
As the development of automobiles, people pay more and more attention to the comfort inside the cabin. A conventional internal combustion engine vehicle utilizes waste heat of an internal combustion engine and heat from exhaust gas of the engine to heat the cabin. In normal driving state the temperature of circulating water in the internal combustion engine vehicle is generally above 80 degrees, which may basically meet heating requirements of the cabin under various conditions. However, the power of an electric vehicle is mainly provided by a motor, and the temperature of cooling circulating water in the electric vehicle is only 50 degrees, and the amount of heat is very small. On the other hand, multiple heat generating components are provided inside the electric vehicle, such as a motor frequency converter and batteries, which need to be cooled by using corresponding heat dissipation devices, for ensuring that the heat generating components can operate within an allowable temperature range.
In the prior art, in order to keep the temperature inside the cabin of an electric vehicle at a level comfortable for human body, a variety of ways have been used in the prior art to provide heat for the cabin, such as: 1. using an independent heat source, i.e., heating with PTC or fuels, such as gasoline, kerosene, and ethanol; 2. recovering the waste heat of components assisted with the independent heat source; 3. using a heat pump to ensure that the temperature inside the cabin is always kept within a comfortable temperature range. On the other hand, in order to ensure that the heat generating components operate within a normal temperature range, an air-cooled radiator cooperated with water circulation is usually adopted to cool the components in the prior art.
However, more energy of batteries would be consumed, thereby reducing the driving mileage of the vehicle if the independent heat source among the above various heating ways, such as PTC, is used to provide heat. If the fuel is used to provide heat, not only the heating efficiency is low, but also the environment would be polluted and the load of the vehicle would be increased. Besides, since a separate radiator is needed for cooling the heat generating components, not only the heat is not utilized efficiently but also the cooling effect for the heat generating components is also poor in the case of high environmental temperature, and therefore, the heat generating components may not be controlled to operate under an optimum temperature. In case of recovering the waste heat of devices assisted with the independent heat source, although the heat from the heat generating components is utilized, the problem resulted from the independent heat source still exist and the problem of cooling the heat generating components still exist. If the heat pump is used to adjust the temperature in the cabin, the problem of utilizing the heat of the heating elements and the problem of cooling the heating elements still exist.
Therefore, it has become technical problems to be solved by those skilled in the art that how to improve the reasonableness of using the heat from heat generating components of the electric vehicle and the cooling effect of the heat generating components and how to improve the comfort in the cabin of the electric vehicle so as to achieve the overall management of the heat system of the electric vehicle.